Posted
by
samzenpus
on Thursday June 28, 2012 @02:50PM
from the cloudy-with-a-chance-of-destruction dept.

The Bad Astronomer writes "Using a combination of Hubble and Swift observations, astronomers have apparently witnessed some of a planet's atmosphere being peeled away by a powerful stellar blast. HD 189733b orbits its star just 4 million km from the surface, and a few hours after Swift detected a big X-ray flare from the star, Hubble data revealed a big jump in hydrogen absorption as the planet transited the star. This indicates the planet's atmosphere was blasted off by the flare to the tune of a thousand tons of hydrogen per second. The planet is so hot it probably already loses a substantial amount of air to space all the time, but this spike is the first time a change in an exoplanet's atmosphere has been detected."